EFFECT OF POTASSIUM FERTILIZER ON THE GROWTH AND YIELD OF THREE WHEAT VARIETIES

A field experiment was carried out during the winter season of 2021-2022 in the Nuaimiya area of Fallujah City, Anbar Governorate, to study the effect of three potassium levels on the growth and yield of the wheat crop. The experiment was conducted using a randomized complete block design (RCBD) according to the arrangement of the split-plot with three replicates. The main plots included three varieties of wheat (Ibaa 99, Al-Rasheed, and Abu Ghraib-3), while the sub-plots included three levels of potassium: 0, 100, and 200 kg K ha-1. The results showed the superiority of the Al-Rasheed variety in each of the following: flag leaf area (46.13 cm²), spike length (14.8 cm), number of spikes per square meter (416.1 spikes m-2), number of grains per spike (52.33 grains spike-1), and total grain yield (4.963 tons ha-1). In contrast, the Ibaa 99 variety gave the highest average plant height of 121.11 cm. The Abu Ghraib-3 variety recorded the highest average weight of 1000 grains at 47.8 g. Potassium fertilizer levels significantly affected most growth and yield traits. The 200 kg K ha-1 level gave the highest means for plant height (119.63 cm), flag leaf area (41.51 cm²), spike length (13.65 cm), number of spikes per square meter (417.0 spikes m-2), number of grains per spike (55.22 grains spike-1), and total grain yield (5.004 tons ha-1). There was a significant interaction between the Ibaa 99 variety and the 200 kg K ha-1 level of potassium fertilizer in plant height, and between the Al-Rasheed variety and the same level in flag leaf area, spike length, number of spikes per square meter, and number of grains per spike.